FIG. 7 is a circuit diagram illustrating a configuration of an active balun circuit for comparison.
The circuit illustrated in FIG. 7 is an example of the active balun circuit to generate differential signals having phases of 180 degrees and 0 degrees from a single-end high frequency signal received through an antenna in a high frequency circuit (see Patent Literature 1).
In this active balun circuit, an output of a CG (common•Gate) transistor 4 having a gate thereof grounded, which has been obtained from an input signal at an input terminal 1, is phase-adjusted by a transistor 5, thereby outputting a signal with a phase of 0 degrees to an output terminal 2. Further, an output of a CS (common•Source) transistor 6 having a source thereof grounded, which has been obtained from the input signal at the input terminal 1, is output to an output terminal 3 as an inverted signal with a phase of 180 degrees. Differential signals are thereby obtained.